The ultimate and continuing objective of this research is the understanding of the pathogenesis of acne in order to improve preventive and therapeutic measures. During the current year research goals include: 1. Continued study of the significance of altered amounts of C18 dienoic fatty acids in acne. 2. Further definition of the factors controlling lipogenesis in the sebaceous gland using in vitro incubations of punch biopsy specimens rich in sebaceous glands. Determination of the kinetics of sebum transport within the follicle. 4. Measurement of sebum composition in relation to dietary deprivation. 5. Measurement of the microflora and lipid composition in patients with acne being treated with antibiotics. BIBLIOGRAPHIC REFERENCES: Downing, D.T., Strauss, J.S. Ramasastry, P., Abel, M., Lees, C.W., and Pochi, P.E.: Measurement of the time between synthesis and surface excretion of sebaceous lipids in sheep and man. J. Invest. Dermatol. 64:215-219, 1975. Strauss, J.S., Pochi, P.E., and Downing, D-T.: Skin lipids and acne. Annual Review of Medicine 26:27-32, 1975.